Control valve mechanism for pneumatic drills



Nov. 14, 1933.

C. A. HULTQUIST CONTROL VALVE MECHANISM FOR PNEUMATIC DRILLS Filed NOV, 14. 1952 Ennentor HA ELES A #04 rqw/sr Q 45 QM Gttorneg Patented Nov. 1 4, 1933 coiv'rnoL VAL My invention relates to control valvemechanism for pneumaticdrills; and the objects ofmy invention'are: I

First,- to' provide a mechanism of 7 this class in' 5 which a singleslide'valve.controls both the inlet and; exhaust portsconnected with'both ends of the; cylinder; the valve'andits casingbeingsoarranged that the quantity of air ,admitted'is'mdtered yet ample port :area is available for 'e f-' Vficient discharge of the exhaust;

- Second, to providea mechanism'of thispcla'ssjwhich, although the incoming airis metered, is

so'arrangedas to reducethe frictional losses occasioned by such metering to a minimum wherein a central inlet port is provided which co- 7 acts witha slide valve adapted to, direct the incoming air to'one sideor the other, the port and series of annular grooves 1d;'1c and'lfarranged valve being so arranged that a bearing surface is provided at all times at both sides of tiguous to ,the inlet port; ,c

Fourth, to provide a valve mechanism of this class which is particularly simple and economical.-

.of'manufacture; and, Q. 7 7

Fifth, to provide on the whole a novelty con structedcontrol valve mechanism for pneumatic drills which is durable, efficient in its action and which will not readily order.- V V 1 I Withthese and other objects in view, as will appear hereinafter, myinventionconsistsrof certain novel features of. construction, combination andarrangementpof parts andportions as wi-ll'be hereinafter, described in detail and particularly set forth inthe appended claims, reference being of this'application in which:

Figure 1 isa longitudinalsectional view of a control valvemechanism, parts and portions in-t elevation, and showing adjacent portions of. a: pneumatic, tool fragmentarily; Fig. 2 isa trans-Q verse sectional view through 2 '2' of Fig.7 1;and Fig. 3 is another transverse sectional view through 3-3ofFig. 1.

Likei characters of reference drawing. I Valve casing 1, valve liners 2, slide }valve 3, andcap members 4 constitute the principal parts 'and portions of my novel control valve mechanism v 'for pneumatic..:drills.

--The parts of the pneumatic through which extends the shankiD of mounted within the cylinder A. I

Securedto, one side of the cylinder A is a Third to ;provide}a mechanism of this class,

and condeteriorate ,or; get out of v "nular group of holes 2] registering with and corresponding to the channels 1d, 16 and 1f.

7 drill particularly associated with my control valve mechanism are a, cylinder Av closed at one end. by.;a head member B; and at the other end by a sleeve member C a piston E therethrough paralleling the bore of the'cyli'nder A.. -A valve liner 2 is fitted: in the bore la from each enact the valve casing'l. Each-liner? isihollow and comprises a cylindrical portion 2a and a. flanged-head portion 2b which fits against of the casing l. The slot lb-intersects aninternallythreaded boss lc intowhich the air sup-; ply line is connected. I I The bores of the liners 2 which are coaxial slidaoly receive a slide valve 3. The movement of the slide valve 3 is limited by a cap or head j member l which plug the ends of the valve liners andare'secured therewith itothe casing 1. The bore of the casing. 1. is .provided with a outwardly at either side of the slot lb. 7

i The innermost pair of channels 1d are intersected bynpassages F and G which extend into the corresponding end of 'the casing 1'. L The ins. nerextremities of the'liners 2 are spaced from I each other forming anannular inlet port 20, which registers with' an inlet slot lb in the wall,

the wallof the cylinder A, then along the wall The-bores of the liners-are of equal diameter and are constant throughout 'ex'ceptyfor enlarged I portions adjacent the axial inner ends of the liners which 'tOgBthBIfOIIIlithB inletport2c; The sleeve valvej3 comprises a central disc-member 3a which had to the accompanying'drawing and to the charf acters of reference thereon Which form a part fcrms a close sliding fit with the enlarged portions ofuthetbores and hasgan axial extent greaterthan in diameter-forming apair of relatively deep annular channels 31). i The channels 31) are bordered ,at their axially outward sides by annular flanges Sc-which fit snugly in the smaller diametered or. a 7 normal portions of, the bores.- The weight of therefer to similar I parts and portions throughout'the views ofthe slide' valve may be decreased by providing addi-v tional grooves or channels 3d between the flanges the inletport 2c, so that the discBdbears on both I sides of the inlet, port at all times. At each side "of the central disc ,3athe slide valve is reduced 3c andiextremities of the sleeve valve. Insuch" case the sleeveivalv'e is provided, atiits extremities with bearing flanges 3c. The end faces of the sleeve valve. are provided with small bosses 3f; which form with the inner endsof the caps 4 small chambers for the admission of air used to shift the. sleeve valve, aswill'bedescribed here inafterw H -1 c In eachkside: of the central ridge or disc 311 are -cut:a pair'of notches 39. The notches are so arranged that either one pair or the-other regis-x ter with theintake ports 20 and form with theaxially: inner extremities of the linears meter valves adapted to regulate the quantity of air admitted. The movement of the slide valve is restricted sothat the channels 3b do not register :directly with the intake port 2c'therefore the air 5 flows axially through the meter valves formed by the notches 3g. After the valve shifts so that the capacity of the communications between the intake port 20 and the notches 3g is equal to or exceeds the capacity of said meter valves, further axial movement of the slide valve .within its stroke does not vary the flow through said metervalves. Hence, the valve ports may be made relatively large, limited only by the axial extent of the notches 3g and stroke of the slide valve. When either of the channels 31) are in communication with the intake port '20 through the nel 3b is functioning to connect its passage with a source of air supply, the other channel 3b connects the remaining groove 1d and its passage or Gwith the adjacent groove 1c. The grooves 1e intersect the side wall'of the casing land constitute outlet ports. j

The remaining or outermost grooves 11 are connected with passages H and I which cross but so do not intersect each other and communicate with the cylinder A near its central portion. These passages conduct air from the cylinder to the ends of the sleeve valve so as to shift the valve from one extreme position to the other.

Though I have shownand described a particular construction,- combination and arrangement of parts and portions, I do not'wish to be limited to this particular construction, combination and arrangement, but desire to include in the scope of my invention the construction, combinationand arrangement substantially as set forth in the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. Ina control valve mechanism for pneumatic drills, a casing having a bore therethrough, an annularintake port surrounding and intersecting said bore, and other ports also intersecting said bore, a slide valve mounted in said bore, in-

cluding a disc bridging'said intake port so as to-bear on both'sides thereof, channels at. either axial side thereof for linking the several ports,

and spaced apart metering notches formed in the. sides of said disc for communicating with said intake port and arranged to direct air therefrom axially into either of said channels.

2. In a control valve mechanism for pneumatic drills, a casing, having a bore" therethrough, apair of tubular liners positioned in said boreand terminating with their inner'ends in contiguous but spaced relation iorming'an annular intake port, said liners having other ports intermediate their ends, a slide valve mounted in said liners,

V including a disc bridging said intake port so as to bear on bothsides thereof, channels at either axial side thereof for linking'the several ports, and spaced apart metering notches iormed in the sides of said disc for communicating with it said intake port and arranged to direct air therefrom axially into either of said channels.

3. In a control valve mechanism for pneumatic bore and a plurality of ports, including an intake port, therein communicating with the cylinder of a pneumatic drill so as to effect operation of a hammer or piston therein, a slide valve mounted in said bore, including a disc bridging said in- ,take port so as to bear on both sides thereof,

channels at either axial side thereof for linking the several ports, and spaced apart metering notches formed in the sides of said disc for communicating with said intake port and arranged to direct air'therefrom axially into either of said channels.

4. In a control valve mechanism for pneumatic 1 drills-the combination with a casing having a bore and a plurality of ports, including an intake port, therein communicating with the cylinder of a pneumatic drill so as to effect operation of a hammer or piston therein, a pair of tubular liners positioned within said bore and terminating with their inner ends in contiguous but spaced relation forming an intake aperture regis tering with said intake port, said liners provided with other'apertures registering with the other ports, a slide valve mounted in said'liners, including a disc bridging said intake'port so as to bear on both sides thereof, channels at either axial side thereof for linking the several ports, and spaced, apart metering notches formed in the sides of said disc for communicating with said intake port and arranged to direct air therefrom axially into either of said channels.

5. In a control valve mechanism for pneumatic drills, the combination with a casing having a bore and a plurality of ports therein comunicating with the cylinder of a rock drill so as to effect operation of a hammer or piston therein, and tubular liners inserted in the bore wherein the liners "have apertures registering with the several ports, of a slide valve mounted in said tubular liners, having a disc portion adapted to register with and bridge the aperture and corresponding port forming the intake, annular channels on either side of said disc arranged to connect adjacent ports, and notches formed in the axial sides of' said disc arranged to form a communication between said intake port and one or the other of said channels 6. In a control valve mechanism for pneumatic drills, the combination with a casing having a bore and a plurality of ports therein communieating with the cylinders of a rock-drill so as to eiiect operation of a hammer or'piston therein, of a pair of liners adapted to be inserted in the bore with their inner ends in spaced relation forming an intake aperture, each of said liners being tubular having a largerdiametered portion at its inner end, and a smaller diametered portion outwardly therefrom and intersected by otherapertures, said apertures registering with the'ports in said casing, a cylindrical slide valve mounted-therein including a central disc arranged to fit the larger diameteredv portions of the liners and bridge the intake aperture formed therebetween, and discs arranged to fit .the smaller diametered portions of the liners, there Ac being formed between said discs a pair of channels adapted to connect adjacent'apertures, and notches in the sides and periphery of said central discv arranged to uncover one side or the other of said intake aperture for directingthe air axially into one or the other of said channels.

CHARLES A. I-IULTQUIST. 

